Gigi's post came a few hours after Liam Payne also took to social media to wish Zayn happy birthday.

Taking to Twitter on Thursday evening, Liam sent Directioners into a frenzy as he wrote: "@zaynmalik Happy birthday bro! Hope all is well and you have a good day celebrating it (sic)"

Not surprisingly, fans immediately responded with a wave of love for the gesture, with many hinting they were crying tears of joy.

Zayn previously insisted he had rarely spoken to the rest of One Direction - which includes Liam, Harry Styles, Louis Tomlinson and Niall Horan - since he quit the group in March 2015, so perhaps it is no surprise his other ex-bandmates haven't reached out to him on Twitter on his special day.

Gigi Hadid Zayn Malik (Image: Copyright unknown)

He previously said: "The truth is I haven't spoken to any of the boys at all really, I spoke to Liam a bit and that's just the way it is.

"I did try to reach out to a couple of people and they didn't get back to me, but then publicly, when they were asked questions about it, said that they'd spoken to me and that we were friends.

"But that's not the case, I tried to reach out and be their friend but they haven't even replied to any of my calls or texts."

Zayn Malik and Gigi Hadid attend the Givenchy show as part of the Paris Fashion Week Womenswear Spring/Summer 2017 on October 2, 2016 in Paris, France (Image: Getty Images Europe)